The risk of infection for patients with heart pacemakers and defibrillators has more than doubled since the early 1990s and it may be because these patients are sicker than they used to be, U.S. researchers report. They analyzed a national database of hospital discharge records and found that infections related to cardiac electrophysiological devices (CIEDs) increased by 210 percent between 1993 and 2008. CIEDS include permanent pacemakers and implantable cardioverter defibrillators (ICDs).